In a speech in Berlin, he’s gone and compared governments who broke fiscal rules to the Lowest of the Low in German society, the Untouchables for whom no contempt is profound enough. Yep, that’s right: jaywalkers.

“Unfortunately, the member states showed as much respect for the debt rules of the Maastricht Treaty and the Stability and Growth Pact as modern city-dwellers show to red lights at pedestrian crossings,” the august head of Germany’s central bank said.

We’ve all been there. Breathes there the man with soul so dead, that hath not, at one stage, ventured to cross a completely deserted German street while the little red girl sign was still showing? And every time, did there not materialize, out of nowhere, a sanctimonious fellow pedestrian to tut-tut, or worse?

In the context of Mr. Weidmann’s speech, it’s hard to quibble with the blatant disregard for fiscal rules that led the euro zone to where it is today. But there will be some who would like to think that, as he prepares to assume the role of co-supervisor for the euro zone’s largest banks, he won’t always be so quick to endorse the slavish obedience to rules over the exercise of common sense.

In an illuminating contrast only a few hours earlier in London, Paul Tucker, the Bank of England’s departing head of financial stability issues, had warned a parliamentary committee at some length that regulators shouldn’t be “dazzled by rules” because no set of rules is going to insure a financial system against future bank failures. Mr. Tucker repeated his mantra that judgment and discretion will consequently have to be the maincharacteristics of supervisory regimes in future.

However, there may be less distance between the two views than meets the eye. Neither Mr. Tucker nor Mr. Weidmann is inclined to give banks the benefit of the doubt just because they hit certain capital ratios, or limits on large exposures. What both are more afraid of is the risk of the ECB’s upcoming Asset Quality Review going the same way of the European Banking Authority’s discredited stress tests, which were reduced, under political pressure, to a simple ‘pass-fail’ exercise with the hurdle set deliberately low.

Mr. Weidmann would surely relish using his discretion to ensure a more thorough audit of euro-zone banks’ balance sheets. After all, the superficial observance of Basel II rules didn’t stop IKB, Hypo Real Estate and a string of Landesbanken blowing up on the joint watch of the Bundesbank and its colleagues at Bafin.

The trouble is, the euro zone has almost always erred on the side of indulgence in enforcing its rules over the last four years. The EBA and ECB are both promising some major details of their approach to the AQR and ensuing stress test later this month. We shouldn’t have too long to wait to see whether, this time at least, the ECB going to be on the law-abiding pedestrian’s side, rather than the jaywalkers’.